1. Field of the Invention
The present invention relates to a projection type video display device which projects an enlarged image on a screen to display an image, and a projection optical unit.
2. Description of the Related Art
In a color video display device which enlarges and projects an image of a video display element on a screen by means of a projection optical unit, it is demanded that a depth of the device be reduced while obtaining an enlarged video having a sufficient size on the screen. To realize this, as described in, for example, JP-A-5-134213 (Patent Document 1), JP-A-2000-162544 (Patent Document 2), and JP-A-2002-357768 (Patent Document 3), there is known a projection optical unit having such a constitution as to enlarge and project the image on the screen from an oblique direction.